Abstract

The current thesis examined the influence of acceptance, suppression and other
coping strategies on levels of physiological and self-reported anxiety, induced
experimentally by academic tasks. The research program comprised four automated
experimental studies. Chapter 1 provides a review of the available literature on relaxation
techniques, including empirical evidence of their utility, theories of underlying processes
and the role of various psychological strategies. Chapter 2 comprises Experiment 1 (n=60)
that compared five intervention components with placebo. The first part of the intervention
comprised Progressive Muscle Relaxation (PMR) Training or Placebo, coupled thereafter
with a specific strategy that was intended to supplement the PMR Training/Placebo in
terms of reducing participant anxiety induced by the academic test. Specifically,
participants were instructed to engage in acceptance or suppression (or placebo) in
response to task-induced anxiety.
Mean skin conductance level (SCL) increased for all conditions from Baseline-
Test, suggesting that the target academic test did increase physiological anxiety, as
predicted. Subjective anxiety also increased significantly and subjective relaxation
decreased significantly from pre- to post-experiment. Mean SCL decreased for all
conditions from Test-Post-test/intervention, suggesting some small influence for the
interventions and/or for practice (because Placebo also changed). Although we predicted
that the Acceptance Instruction would be associated with smaller increases in anxiety than
both Suppression and Placebo, the data from Experiment 1 indicated no significant effect
for condition, hence failing to confirm this hypothesis. However, Placebo+Acceptance
showed the smallest increase in anxiety from Baseline-Test, the largest decrease from
Test-Post-test and the smallest overall increase from Baseline-Post-test. Nonetheless, the
strong similarities across conditions made comparisons between the first and second parts
of the interventions difficult.
For Experiment 2 (n=20) reported in Chapter 3, a new type of anxiety-inducing
academic test was constructed that involved an on-going stressor and the repeated
introduction of a visual stimulus (a neutral image), which the Suppression group only (not
Control) were instructed to suppress. In theory, the continued effort of suppressing the
image might serve to increase anxiety levels during the task for the Suppression group,
relative to participants who are not instructed to suppress the image. A secondary aim of
the study was to examine whether the instruction to suppress the stimulus affected
participants’ habituation to its appearance and we predicted that habituation would be
disrupted in Suppression, but not in Control. Mean SCL between Baseline and Test
increased significantly for participants in the Suppression Condition, but not in Control.
The study also included analyses of skin conductance response (SCR) as a means of
measuring habituation to the presence of the visual stimulus. The dominant pattern of
responding in Control was Habituation. In contrast, response patterns in Suppression were
either Inconsistent or indicative of Increasing Arousal.
Experiment 3 (n=80) reported in Chapter 4 attempted to examine the efficacy of
acceptance and suppression interventions, using a modified version of the task protocol
developed in Experiment 2. We also examined differences in anticipatory arousal and
event arousal in response to the discreet stimulus presentations. The study also included
Mindfulness and Endurance Interventions, which are topographically similar to
acceptance. The results from Experiment 3 confirmed some of our predictions. First, we
predicted that Suppression and Placebo would be less effective at diminishing anxiety than
Mindfulness and Acceptance and indeed Acceptance was the only condition that showed
decreased physiological anxiety and differed significantly from the other two conditions
between Tests 1 and 2. Analyses of the anticipatory arousal data indicated that
Mindfulness, Suppression and Placebo decreased, while Acceptance and Endurance
increased. On event arousal, all participants increased, with the largest recorded on
Mindfulness, Suppression and Endurance. The differences between anticipatory and event
arousal that occurred between conditions indicate that some strategies may result in
expectation of decreased arousal prior to an event (i.e. reduced anticipatory arousal), but
increased arousal in response to the event itself (i.e. increased event arousal), while other
strategies have the opposite effect.
Experiment 4 (n=95) reported in Chapter 5 attempted to examine the impact of
expectation on the efficacy of acceptance and suppression, as well as the other strategies
examined in Experiment 3. Experiment 4 was identical to the previous study, with the
exception that the interventions were condensed and presented to participants as short
strategies that were "proven to work". The primary aim of this modification was to
explicitly highlight the possible influence of expectation on relaxation. We predicted that
expectation would reduce the efficacy of Acceptance resulting in increased anxiety and
exacerbate the effects of Suppression resulting in larger increases in anxiety from pre- to
post-intervention than all other conditions. We made no specific predictions in relation to
the other strategies. While the previously positive outcomes associated with Acceptance
were reduced, no significant differences were found between conditions. In addition the
largest increase in arousal was observed in the Mindfulness Condition, as opposed to
Suppression. As such, we failed to confirm our hypotheses. Differences between
anticipatory and event arousal were observed; however, patterns were different from those
recorded in the previous study.
The current research extends previous work on the utility of acceptance and
suppression and is the first to examine the role of acceptance in a relaxation context.
Overall, the findings provide evidence for the utility of acceptance as a relaxation strategy
and support previous evidence that suppression can lead to increased arousal, even where
the intent is to relax